Using a large hollow drill, the WAIS Divide Ice Core Drilling team collected a 3,500-meter-long ice core, or sample of ice, from the West Antarctic Ice Sheet. Because of the weight of the overlying snowpack, snow that falls and accumulates on ice sheets re-crystallizes and forms annual layers over time. The ice core recovered during the project had annual resolution, or distinct yearly markings, for the past 40,000 years!
In ice sheets, the compression of snow traps small bubbles of air in the layers of ice. By measuring concentrations of greenhouse gasses and non-greenhouse gasses and their isotopes trapped within bubbles in the ice, the team developed climate records dating back to 100,000 years before present.
This ice core provided the first Southern Hemisphere climate and greenhouse gas records of comparable time, resolution, and duration to ice cores previously recovered in Greenland. The ice core enabled scientists to make detailed comparisons of greenhouse gas concentrations and environmental conditions between the Northern and Southern hemispheres with a greater level of detail than previously possible. The biology of the ice collected was also investigated.
Learn more about this process here
The research team was based at the West Antarctic Ice Sheet (WAIS) drill site, in western Antarctica. The WAIS divide sits on top of 3,485 meters of ice, thicker than 9 Empire State Buildings stacked on top of one another! The WAIS is classified as a marine-based ice sheet, meaning that its bed lies well below sea level and its edges flow into floating ice shelves. The WAIS is bounded by the Ross Ice Shelf, the Ronne Ice Shelf, and outlet glaciers that drain into the Amundsen Sea.
Heidi Roop grew up exploring the formerly glaciated landscape of Wisconsin, and today continues her love for studying glaciers and climate variability through research in Antarctica and alpine regions around the world. Spending the austral summer of 2010-2011 in Antarctica, it will be her second season working as a part of the West Antarctic Ice Sheet (WAIS) Divide project. When she is not in Antarctica, she works throughout the Sierra Nevada studying climate variability and hydrology for the United States Geological Survey.
Bruce Vaughn is the Co-Founder and Manager of the Stable Isotope Lab at the Institute of Arctic and Alpine Research (INSTAAR) (http://instaar.colorado.edu/) at the University of Colorado. The Stable Isotope Lab is devoted to studying biogeochemical processes that control environmental change on human timescales, and works to develop new techniques for measuring environmental stable isotopes. A Field Leader for the project, Mr. Vaughn has extensive research experience worldwide, including: Greenland, Antarctica, equatorial Pacific, Alaska, Ecuador, and the Cascades and Rocky Mountains.
Ken Taylor is a Research Professor at the Desert Research Institute in Reno, Nevada and the Principal Investigator and Chief Scientist for the WAIS Divide Ice Core Drilling Project. Dr. Taylor has worked with ice cores in Greenland and Antarctica, and has also spent time traveling around the world studying water quality issues.
A PhD candidate at Scripps Institution of Oceanography in La Jolla, CA, Anais Orsi studies the history of climate by analyzing gases in air bubbles trapped in ice cores. She has been involved with WAIS-divide for three years. When she is not in Antarctica, she melts ice samples in her lab to release the gases, to learn about West Antarctic climate during the last 1,000 years.